Universal joints, such as the yoke and spider type, typically have two forked coupling halves or yokes which are pivotably mounted to a crossed-pin member or spider for rotation about two axes oriented at right angles to each other. Each arm of each yoke is pivotably mounted to an end of the crossed-pin member by trunnion bearings that have a generally cup-shaped outer race press-fitted within a recess of the yoke arm about the pin end, with a set of needle or roller bearings arranged annularly about the pin end within the race. In order to service the joint, or replace or repair a bearing, it is necessary to remove it from its press-fitted placement within the yoke arms. Heretofore, this has typically been done by unthreading the bolts from both trunnion bearings mounted to the arms of one yoke and then striking that yoke as with a sledgehammer to move it axially along one pin of the crossed-pin member. As this is done the cup-shaped outer race of the bearing is brought into engagement with an end of the pin whereby further movement of the yoke causes that pin end to push the bearing outer race out of its press-fitted location within the yoke arm.
The just-described procedure has had pronounced disadvantages and limitations. For example, the use of a sledgehammer is often limited by spacial restrictions about the universal joint. For instance, with automobiles and trucks its location is often difficult to access and spacially restricted which limits hammer travel distance and direction. The striking of a joint yoke also tends to place a torque upon the crossed-pin member or spider which can itself damage one or both of the trunnion bearings or a bearing seal.
Heretofore, apparatuses or tools have been devised to aid in the removal of trunnion bearings from universal joints. These devices, however, often have been designed merely to insure that the force of a sledgehammer is imparted substantially coaxially with respect to one of the pins of the universal joint's crossed-pin member. Furthermore, the devices have typically been of a configuration such as to require their being mounted completely about a universal joint. For example, U.S. Pat. No. 4,120,082 disclosed a universal drive shaft service kit of such a type which is mounted about opposite sides of a joint and which has an impact knob for communicating a shock force resulting from the impact of a hammer onto a trunnion bearing. Again, spacial restrictions often found to be present within the environs of a universal joint render the use of such devices impractical and cumbersome.
It therefore would be advantageous to devise an apparatus and method for removing trunnion bearings from universal joints in a manner that would overcome these disadvantages and limitations of the prior art. It is this task to which the present invention is primarily directed.